We have recently developed operative procedures in which a bipedicle flap of cervical skin and platysma muscle can be fashioned to serve as either: 1) a substitute larynx, or 2) a substitute for up to 6 cm. of resected trachea. These procedures have been succesfully applied in patients. We plan to evaluate the physical quality of function of the substitute larynx in humans and experimental animals (mini-pigs) by the use of simultaneous records of movement, sound, air pressures and air flow to determine the shape of the new larynx and glottis which will produce the best vocal quality. We also wish to determine in experimental animals if the cervical flap will serve to replace the entire trachea for long periods of time.